// Copyright 2017 Google Inc. All Rights Reserved.
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//     http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package main

import (
	"context"
	"flag"
	"fmt"
	"log"
	"net/http"
	"os"
	"os/signal"
	"syscall"
)

var (
	httpAddr string
)

func main() {
	flag.StringVar(&httpAddr, "http", "127.0.0.1:80", "HTTP service address")
	flag.Parse()

	fmt.Println("Starting helloworld...")

	mux := http.NewServeMux()
	mux.HandleFunc("/", httpHandler)
	httpServer := http.Server{Addr: httpAddr, Handler: mux}

	go func() {
		log.Fatal(httpServer.ListenAndServe())
	}()

	signalChan := make(chan os.Signal, 1)
	signal.Notify(signalChan, syscall.SIGINT, syscall.SIGTERM)
	<-signalChan

	log.Printf("Shutdown signal received shutting down gracefully...")

	httpServer.Shutdown(context.Background())
}
